Notebook computers are generally capable of using internal rechargeable batteries and/or external rechargeable batteries (travel batteries) as power supplies. Notebook computers may also be docked in a docking station alone or with an external battery attached thereto, which enables the batteries to be charged from an external power supply. Typically, the charging cycle for both internal and external batteries is controlled by a circuit inside the notebook computer. However, in order to keep cost and weight low for the notebook computer, the charging components are capable of handling only enough current to charge one battery, thereby resulting in an extended delay if more than a single battery needs charging.